content: /**
   * Copyright (c) 2016-present, RxJava Contributors.
   *
   * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in
   * compliance with the License. You may obtain a copy of the License at
   *
   * http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software distributed under the License is
   * distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See
   * the License for the specific language governing permissions and limitations under the License.
   */
  
  package io.reactivex.observable.internal.operators;
  
  import static org.junit.Assert.*;
  
  import java.lang.reflect.Method;
  import java.util.*;
  import java.util.concurrent.*;
  import java.util.concurrent.atomic.*;
  
  import org.junit.*;
  
  import io.reactivex.common.*;
  import io.reactivex.common.exceptions.*;
  import io.reactivex.common.functions.*;
  import io.reactivex.common.internal.functions.Functions;
  import io.reactivex.observable.*;
  import io.reactivex.observable.Observable;
  import io.reactivex.observable.observers.TestObserver;
  import io.reactivex.observable.subjects.*;
  
  public class ObservableConcatMapEagerTest {
  
      @Test
      public void normal() {
          Observable.range(1, 5)
          .concatMapEager(new Function<Integer, ObservableSource<Integer>>() {
              @Override
              public ObservableSource<Integer> apply(Integer t) {
                  return Observable.range(t, 2);
              }
          })
          .test()
          .assertResult(1, 2, 2, 3, 3, 4, 4, 5, 5, 6);
      }
  
      @Test
      @Ignore("Observable doesn't do backpressure")
      public void normalBackpressured() {
  //        TestObserver<Integer> ts = Observable.range(1, 5)
  //        .concatMapEager(new Function<Integer, ObservableSource<Integer>>() {
  //            @Override
  //            public ObservableSource<Integer> apply(Integer t) {
  //                return Observable.range(t, 2);
  //            }
  //        })
  //        .test(3);
  //
  //        ts.assertValues(1, 2, 2);
  //
  //        ts.request(1);
  //
  //        ts.assertValues(1, 2, 2, 3);
  //
  //        ts.request(1);
  //
  //        ts.assertValues(1, 2, 2, 3, 3);
  //
  //        ts.request(5);
  //
  //        ts.assertResult(1, 2, 2, 3, 3, 4, 4, 5, 5, 6);
      }
  
      @Test
      public void normalDelayBoundary() {
          Observable.range(1, 5)
          .concatMapEagerDelayError(new Function<Integer, ObservableSource<Integer>>() {
              @Override
              public ObservableSource<Integer> apply(Integer t) {
                  return Observable.range(t, 2);
              }
          }, false)
          .test()
          .assertResult(1, 2, 2, 3, 3, 4, 4, 5, 5, 6);
      }
  
      @Test
      @Ignore("Observable doesn't do backpressure")
      public void normalDelayBoundaryBackpressured() {
  //        TestObserver<Integer> ts = Observable.range(1, 5)
  //        .concatMapEagerDelayError(new Function<Integer, ObservableSource<Integer>>() {
  //            @Override
  //            public ObservableSource<Integer> apply(Integer t) {
  //                return Observable.range(t, 2);
  //            }
  //        }, false)
  //        .test(3);
  //
  //        ts.assertValues(1, 2, 2);
  //
  //        ts.request(1);
  //
  //        ts.assertValues(1, 2, 2, 3);
  //
  //        ts.request(1);
  //
  //        ts.assertValues(1, 2, 2, 3, 3);
  //
  //        ts.request(5);
  //
  //        ts.assertResult(1, 2, 2, 3, 3, 4, 4, 5, 5, 6);
      }
  
      @Test
      public void normalDelayEnd() {
          Observable.range(1, 5)
          .concatMapEagerDelayError(new Function<Integer, ObservableSource<Integer>>() {
              @Override
              public ObservableSource<Integer> apply(Integer t) {
                  return Observable.range(t, 2);
              }
          }, true)
          .test()
          .assertResult(1, 2, 2, 3, 3, 4, 4, 5, 5, 6);
      }
  
      @Test
      @Ignore("Observable doesn't do backpressure")
      public void normalDelayEndBackpressured() {
  //        TestObserver<Integer> ts = Observable.range(1, 5)
  //        .concatMapEagerDelayError(new Function<Integer, ObservableSource<Integer>>() {
  //            @Override
  //            public ObservableSource<Integer> apply(Integer t) {
  //                return Observable.range(t, 2);
  //            }
  //        }, true)
  //        .test(3);
  //
  //        ts.assertValues(1, 2, 2);
  //
  //        ts.request(1);
  //
  //        ts.assertValues(1, 2, 2, 3);
  //
  //        ts.request(1);
  //
  //        ts.assertValues(1, 2, 2, 3, 3);
  //
  //        ts.request(5);
  //
  //        ts.assertResult(1, 2, 2, 3, 3, 4, 4, 5, 5, 6);
      }
  
      @Test
      public void mainErrorsDelayBoundary() {
          PublishSubject<Integer> main = PublishSubject.create();
          final PublishSubject<Integer> inner = PublishSubject.create();
  
          TestObserver<Integer> ts = main.concatMapEagerDelayError(
                  new Function<Integer, ObservableSource<Integer>>() {
                      @Override
                      public ObservableSource<Integer> apply(Integer t) {
                          return inner;
                      }
                  }, false).test();
  
          main.onNext(1);
  
          inner.onNext(2);
  
          ts.assertValue(2);
  
          main.onError(new TestException("Forced failure"));
  
          ts.assertNoErrors();
  
          inner.onNext(3);
          inner.onComplete();
  
          ts.assertFailureAndMessage(TestException.class, "Forced failure", 2, 3);
      }
  
      @Test
      public void mainErrorsDelayEnd() {
          PublishSubject<Integer> main = PublishSubject.create();
          final PublishSubject<Integer> inner = PublishSubject.create();
  
          TestObserver<Integer> ts = main.concatMapEagerDelayError(
                  new Function<Integer, ObservableSource<Integer>>() {
                      @Override
                      public ObservableSource<Integer> apply(Integer t) {
                          return inner;
                      }
                  }, true).test();
  
          main.onNext(1);
          main.onNext(2);
  
          inner.onNext(2);
  
          ts.assertValue(2);
  
          main.onError(new TestException("Forced failure"));
  
          ts.assertNoErrors();
  
          inner.onNext(3);
          inner.onComplete();
  
          ts.assertFailureAndMessage(TestException.class, "Forced failure", 2, 3, 2, 3);
      }
  
      @Test
      public void mainErrorsImmediate() {
          PublishSubject<Integer> main = PublishSubject.create();
          final PublishSubject<Integer> inner = PublishSubject.create();
  
          TestObserver<Integer> ts = main.concatMapEager(
                  new Function<Integer, ObservableSource<Integer>>() {
                      @Override
                      public ObservableSource<Integer> apply(Integer t) {
                          return inner;
                      }
                  }).test();
  
          main.onNext(1);
          main.onNext(2);
  
          inner.onNext(2);
  
          ts.assertValue(2);
  
          main.onError(new TestException("Forced failure"));
  
          assertFalse("inner has subscribers?", inner.hasObservers());
  
          inner.onNext(3);
          inner.onComplete();
  
          ts.assertFailureAndMessage(TestException.class, "Forced failure", 2);
      }
  
      @Test
      public void longEager() {
  
          Observable.range(1, 2 * Observable.bufferSize())
          .concatMapEager(new Function<Integer, ObservableSource<Integer>>() {
              @Override
              public ObservableSource<Integer> apply(Integer v) {
                  return Observable.just(1);
              }
          })
          .test()
          .assertValueCount(2 * Observable.bufferSize())
          .assertNoErrors()
          .assertComplete();
      }
  
      TestObserver<Object> ts;
  
      Function<Integer, Observable<Integer>> toJust = new Function<Integer, Observable<Integer>>() {
          @Override
          public Observable<Integer> apply(Integer t) {
              return Observable.just(t);
          }
      };
  
      Function<Integer, Observable<Integer>> toRange = new Function<Integer, Observable<Integer>>() {
          @Override
          public Observable<Integer> apply(Integer t) {
              return Observable.range(t, 2);
          }
      };
  
      @Before
      public void before() {
          ts = new TestObserver<Object>();
      }
  
      @Test
      public void testSimple() {
          Observable.range(1, 100).concatMapEager(toJust).subscribe(ts);
  
          ts.assertNoErrors();
          ts.assertValueCount(100);
          ts.assertComplete();
      }
  
      @Test
      public void testSimple2() {
          Observable.range(1, 100).concatMapEager(toRange).subscribe(ts);
  
          ts.assertNoErrors();
          ts.assertValueCount(200);
          ts.assertComplete();
      }
  
      @SuppressWarnings("unchecked")
      @Test
      public void testEagerness2() {
          final AtomicInteger count = new AtomicInteger();
          Observable<Integer> source = Observable.just(1).doOnNext(new Consumer<Integer>() {
              @Override
              public void accept(Integer t) {
                  count.getAndIncrement();
              }
          }).hide();
  
          Observable.concatArrayEager(source, source).subscribe(ts);
  
          Assert.assertEquals(2, count.get());
  
          ts.assertValueCount(count.get());
          ts.assertNoErrors();
          ts.assertComplete();
      }
  
      @SuppressWarnings("unchecked")
      @Test
      public void testEagerness3() {
          final AtomicInteger count = new AtomicInteger();
          Observable<Integer> source = Observable.just(1).doOnNext(new Consumer<Integer>() {
              @Override
              public void accept(Integer t) {
                  count.getAndIncrement();
              }
          }).hide();
  
          Observable.concatArrayEager(source, source, source).subscribe(ts);
  
          Assert.assertEquals(3, count.get());
  
          ts.assertValueCount(count.get());
          ts.assertNoErrors();
          ts.assertComplete();
      }
  
      @SuppressWarnings("unchecked")
      @Test
      public void testEagerness4() {
          final AtomicInteger count = new AtomicInteger();
          Observable<Integer> source = Observable.just(1).doOnNext(new Consumer<Integer>() {
              @Override
              public void accept(Integer t) {
                  count.getAndIncrement();
              }
          }).hide();
  
          Observable.concatArrayEager(source, source, source, source).subscribe(ts);
  
          Assert.assertEquals(4, count.get());
  
          ts.assertValueCount(count.get());
          ts.assertNoErrors();
          ts.assertComplete();
      }
  
      @SuppressWarnings("unchecked")
      @Test
      public void testEagerness5() {
          final AtomicInteger count = new AtomicInteger();
          Observable<Integer> source = Observable.just(1).doOnNext(new Consumer<Integer>() {
              @Override
              public void accept(Integer t) {
                  count.getAndIncrement();
              }
          }).hide();
  
          Observable.concatArrayEager(source, source, source, source, source).subscribe(ts);
  
          Assert.assertEquals(5, count.get());
  
          ts.assertValueCount(count.get());
          ts.assertNoErrors();
          ts.assertComplete();
      }
  
      @SuppressWarnings("unchecked")
      @Test
      public void testEagerness6() {
          final AtomicInteger count = new AtomicInteger();
          Observable<Integer> source = Observable.just(1).doOnNext(new Consumer<Integer>() {
              @Override
              public void accept(Integer t) {
                  count.getAndIncrement();
              }
          }).hide();
  
          Observable.concatArrayEager(source, source, source, source, source, source).subscribe(ts);
  
          Assert.assertEquals(6, count.get());
  
          ts.assertValueCount(count.get());
          ts.assertNoErrors();
          ts.assertComplete();
      }
  
      @SuppressWarnings("unchecked")
      @Test
      public void testEagerness7() {
          final AtomicInteger count = new AtomicInteger();
          Observable<Integer> source = Observable.just(1).doOnNext(new Consumer<Integer>() {
              @Override
              public void accept(Integer t) {
                  count.getAndIncrement();
              }
          }).hide();
  
          Observable.concatArrayEager(source, source, source, source, source, source, source).subscribe(ts);
  
          Assert.assertEquals(7, count.get());
  
          ts.assertValueCount(count.get());
          ts.assertNoErrors();
          ts.assertComplete();
      }
  
      @SuppressWarnings("unchecked")
      @Test
      public void testEagerness8() {
          final AtomicInteger count = new AtomicInteger();
          Observable<Integer> source = Observable.just(1).doOnNext(new Consumer<Integer>() {
              @Override
              public void accept(Integer t) {
                  count.getAndIncrement();
              }
          }).hide();
  
          Observable.concatArrayEager(source, source, source, source, source, source, source, source).subscribe(ts);
  
          Assert.assertEquals(8, count.get());
  
          ts.assertValueCount(count.get());
          ts.assertNoErrors();
          ts.assertComplete();
      }
  
      @SuppressWarnings("unchecked")
      @Test
      public void testEagerness9() {
          final AtomicInteger count = new AtomicInteger();
          Observable<Integer> source = Observable.just(1).doOnNext(new Consumer<Integer>() {
              @Override
              public void accept(Integer t) {
                  count.getAndIncrement();
              }
          }).hide();
  
          Observable.concatArrayEager(source, source, source, source, source, source, source, source, source).subscribe(ts);
  
          Assert.assertEquals(9, count.get());
  
          ts.assertValueCount(count.get());
          ts.assertNoErrors();
          ts.assertComplete();
      }
  
      @Test
      public void testMainError() {
          Observable.<Integer>error(new TestException()).concatMapEager(toJust).subscribe(ts);
  
          ts.assertNoValues();
          ts.assertError(TestException.class);
          ts.assertNotComplete();
      }
  
      @SuppressWarnings("unchecked")
      @Test
      public void testInnerError() {
          // TODO verify: concatMapEager subscribes first then consumes the sources is okay
  
          PublishSubject<Integer> ps = PublishSubject.create();
  
          Observable.concatArrayEager(Observable.just(1), ps)
          .subscribe(ts);
  
          ps.onError(new TestException());
  
          ts.assertValue(1);
          ts.assertError(TestException.class);
          ts.assertNotComplete();
      }
  
      @SuppressWarnings("unchecked")
      @Test
      public void testInnerEmpty() {
          Observable.concatArrayEager(Observable.empty(), Observable.empty()).subscribe(ts);
  
          ts.assertNoValues();
          ts.assertNoErrors();
          ts.assertComplete();
      }
  
      @Test
      public void testMapperThrows() {
          Observable.just(1).concatMapEager(new Function<Integer, Observable<Integer>>() {
              @Override
              public Observable<Integer> apply(Integer t) {
                  throw new TestException();
              }
          }).subscribe(ts);
  
          ts.assertNoValues();
          ts.assertNotComplete();
          ts.assertError(TestException.class);
      }
  
      @Test(expected = IllegalArgumentException.class)
      public void testInvalidMaxConcurrent() {
          Observable.just(1).concatMapEager(toJust, 0, Observable.bufferSize());
      }
  
      @Test(expected = IllegalArgumentException.class)
      public void testInvalidCapacityHint() {
          Observable.just(1).concatMapEager(toJust, Observable.bufferSize(), 0);
      }
  
      @Test
  //    @SuppressWarnings("unchecked")
      @Ignore("Observable doesn't do backpressure")
      public void testBackpressure() {
  //        Observable.concatArrayEager(Observable.just(1), Observable.just(1)).subscribe(ts);
  //
  //        ts.assertNoErrors();
  //        ts.assertNoValues();
  //        ts.assertNotComplete();
  //
  //        ts.request(1);
  //        ts.assertValue(1);
  //        ts.assertNoErrors();
  //        ts.assertNotComplete();
  //
  //        ts.request(1);
  //        ts.assertValues(1, 1);
  //        ts.assertNoErrors();
  //        ts.assertComplete();
      }
  
      @Test
      public void testAsynchronousRun() {
          Observable.range(1, 2).concatMapEager(new Function<Integer, Observable<Integer>>() {
              @Override
              public Observable<Integer> apply(Integer t) {
                  return Observable.range(1, 1000).subscribeOn(Schedulers.computation());
              }
          }).observeOn(Schedulers.newThread()).subscribe(ts);
  
          ts.awaitTerminalEvent(5, TimeUnit.SECONDS);
          ts.assertNoErrors();
          ts.assertValueCount(2000);
      }
  
      @Test
      public void testReentrantWork() {
          final PublishSubject<Integer> subject = PublishSubject.create();
  
          final AtomicBoolean once = new AtomicBoolean();
  
          subject.concatMapEager(new Function<Integer, Observable<Integer>>() {
              @Override
              public Observable<Integer> apply(Integer t) {
                  return Observable.just(t);
              }
          })
          .doOnNext(new Consumer<Integer>() {
              @Override
              public void accept(Integer t) {
                  if (once.compareAndSet(false, true)) {
                      subject.onNext(2);
                  }
              }
          })
          .subscribe(ts);
  
          subject.onNext(1);
  
          ts.assertNoErrors();
          ts.assertNotComplete();
          ts.assertValues(1, 2);
      }
  
      @Test
      @Ignore("Observable doesn't do backpressure so it can't bound its input count")
      public void testPrefetchIsBounded() {
          final AtomicInteger count = new AtomicInteger();
  
          TestObserver<Object> ts = TestObserver.create();
  
          Observable.just(1).concatMapEager(new Function<Integer, Observable<Integer>>() {
              @Override
              public Observable<Integer> apply(Integer t) {
                  return Observable.range(1, Observable.bufferSize() * 2)
                          .doOnNext(new Consumer<Integer>() {
                              @Override
                              public void accept(Integer t) {
                                  count.getAndIncrement();
                              }
                          }).hide();
              }
          }).subscribe(ts);
  
          ts.assertNoErrors();
          ts.assertNoValues();
          ts.assertNotComplete();
          Assert.assertEquals(Observable.bufferSize(), count.get());
      }
  
      @Test
      @Ignore("Null values are not allowed in RS")
      public void testInnerNull() {
          Observable.just(1).concatMapEager(new Function<Integer, Observable<Integer>>() {
              @Override
              public Observable<Integer> apply(Integer t) {
                  return Observable.just(null);
              }
          }).subscribe(ts);
  
          ts.assertNoErrors();
          ts.assertComplete();
          ts.assertValue(null);
      }
  
  
      @Test
      @Ignore("Observable doesn't do backpressure")
      public void testMaxConcurrent5() {
  //        final List<Long> requests = new ArrayList<Long>();
  //        Observable.range(1, 100).doOnRequest(new LongConsumer() {
  //            @Override
  //            public void accept(long reqCount) {
  //                requests.add(reqCount);
  //            }
  //        }).concatMapEager(toJust, 5, Observable.bufferSize()).subscribe(ts);
  //
  //        ts.assertNoErrors();
  //        ts.assertValueCount(100);
  //        ts.assertComplete();
  //
  //        Assert.assertEquals(5, (long) requests.get(0));
  //        Assert.assertEquals(1, (long) requests.get(1));
  //        Assert.assertEquals(1, (long) requests.get(2));
  //        Assert.assertEquals(1, (long) requests.get(3));
  //        Assert.assertEquals(1, (long) requests.get(4));
  //        Assert.assertEquals(1, (long) requests.get(5));
      }
  
      @SuppressWarnings("unchecked")
      @Test
      @Ignore("Currently there are no 2-9 argument variants, use concatArrayEager()")
      public void many() throws Exception {
          for (int i = 2; i < 10; i++) {
              Class<?>[] clazz = new Class[i];
              Arrays.fill(clazz, Observable.class);
  
              Observable<Integer>[] obs = new Observable[i];
              Arrays.fill(obs, Observable.just(1));
  
              Integer[] expected = new Integer[i];
              Arrays.fill(expected, 1);
  
              Method m = Observable.class.getMethod("concatEager", clazz);
  
              TestObserver<Integer> ts = TestObserver.create();
  
              ((Observable<Integer>)m.invoke(null, (Object[])obs)).subscribe(ts);
  
              ts.assertValues(expected);
              ts.assertNoErrors();
              ts.assertComplete();
          }
      }
  
      @SuppressWarnings("unchecked")
      @Test
      public void capacityHint() {
          Observable<Integer> source = Observable.just(1);
          TestObserver<Integer> ts = TestObserver.create();
  
          Observable.concatEager(Arrays.asList(source, source, source), 1, 1).subscribe(ts);
  
          ts.assertValues(1, 1, 1);
          ts.assertNoErrors();
          ts.assertComplete();
      }
  
      @Test
      public void Observable() {
          Observable<Integer> source = Observable.just(1);
          TestObserver<Integer> ts = TestObserver.create();
  
          Observable.concatEager(Observable.just(source, source, source)).subscribe(ts);
  
          ts.assertValues(1, 1, 1);
          ts.assertNoErrors();
          ts.assertComplete();
      }
  
      @Test
      public void ObservableCapacityHint() {
          Observable<Integer> source = Observable.just(1);
          TestObserver<Integer> ts = TestObserver.create();
  
          Observable.concatEager(Observable.just(source, source, source), 1, 1).subscribe(ts);
  
          ts.assertValues(1, 1, 1);
          ts.assertNoErrors();
          ts.assertComplete();
      }
  
      @SuppressWarnings("unchecked")
      @Test
      public void badCapacityHint() throws Exception {
          Observable<Integer> source = Observable.just(1);
          try {
              Observable.concatEager(Arrays.asList(source, source, source), 1, -99);
          } catch (IllegalArgumentException ex) {
              assertEquals("prefetch > 0 required but it was -99", ex.getMessage());
          }
  
      }
  
      @SuppressWarnings({ "unchecked", "rawtypes" })
      @Test
      public void mappingBadCapacityHint() throws Exception {
          Observable<Integer> source = Observable.just(1);
          try {
              Observable.just(source, source, source).concatMapEager((Function)Functions.identity(), 10, -99);
          } catch (IllegalArgumentException ex) {
              assertEquals("prefetch > 0 required but it was -99", ex.getMessage());
          }
  
      }
  
      @SuppressWarnings("unchecked")
      @Test
      public void concatEagerIterable() {
          Observable.concatEager(Arrays.asList(Observable.just(1), Observable.just(2)))
          .test()
          .assertResult(1, 2);
      }
  
      @Test
      public void dispose() {
          TestHelper.checkDisposed(Observable.just(1).hide().concatMapEager(new Function<Integer, ObservableSource<Integer>>() {
              @Override
              public ObservableSource<Integer> apply(Integer v) throws Exception {
                  return Observable.range(1, 2);
              }
          }));
      }
  
      @Test
      public void empty() {
          Observable.<Integer>empty().hide().concatMapEager(new Function<Integer, ObservableSource<Integer>>() {
              @Override
              public ObservableSource<Integer> apply(Integer v) throws Exception {
                  return Observable.range(1, 2);
              }
          })
          .test()
          .assertResult();
      }
  
      @Test
      public void innerError() {
          Observable.<Integer>just(1).hide().concatMapEager(new Function<Integer, ObservableSource<Integer>>() {
              @Override
              public ObservableSource<Integer> apply(Integer v) throws Exception {
                  return Observable.error(new TestException());
              }
          })
          .test()
          .assertFailure(TestException.class);
      }
  
      @Test
      public void innerErrorMaxConcurrency() {
          Observable.<Integer>just(1).hide().concatMapEager(new Function<Integer, ObservableSource<Integer>>() {
              @Override
              public ObservableSource<Integer> apply(Integer v) throws Exception {
                  return Observable.error(new TestException());
              }
          }, 1, 128)
          .test()
          .assertFailure(TestException.class);
      }
  
      @Test
      public void innerCallableThrows() {
          Observable.<Integer>just(1).hide().concatMapEager(new Function<Integer, ObservableSource<Integer>>() {
              @Override
              public ObservableSource<Integer> apply(Integer v) throws Exception {
                  return Observable.fromCallable(new Callable<Integer>() {
                      @Override
                      public Integer call() throws Exception {
                          throw new TestException();
                      }
                  });
              }
          })
          .test()
          .assertFailure(TestException.class);
      }
  
      @Test
      public void innerOuterRace() {
          for (int i = 0; i < 500; i++) {
              List<Throwable> errors = TestCommonHelper.trackPluginErrors();
              try {
                  final PublishSubject<Integer> ps1 = PublishSubject.create();
                  final PublishSubject<Integer> ps2 = PublishSubject.create();
  
                  TestObserver<Integer> to = ps1.concatMapEager(new Function<Integer, ObservableSource<Integer>>() {
                      @Override
                      public ObservableSource<Integer> apply(Integer v) throws Exception {
                          return ps2;
                      }
                  }).test();
  
                  final TestException ex1 = new TestException();
                  final TestException ex2 = new TestException();
  
                  ps1.onNext(1);
  
                  Runnable r1 = new Runnable() {
                      @Override
                      public void run() {
                          ps1.onError(ex1);
                      }
                  };
                  Runnable r2 = new Runnable() {
                      @Override
                      public void run() {
                          ps2.onError(ex2);
                      }
                  };
  
                  TestCommonHelper.race(r1, r2, Schedulers.single());
  
                  to.assertSubscribed().assertNoValues().assertNotComplete();
  
                  Throwable ex = to.errors().get(0);
  
                  if (ex instanceof CompositeException) {
                      List<Throwable> es = TestHelper.errorList(to);
                      TestCommonHelper.assertError(es, 0, TestException.class);
                      TestCommonHelper.assertError(es, 1, TestException.class);
                  } else {
                      to.assertError(TestException.class);
                      if (!errors.isEmpty()) {
                          TestCommonHelper.assertUndeliverable(errors, 0, TestException.class);
                      }
                  }
              } finally {
                  RxJavaCommonPlugins.reset();
              }
          }
      }
  
      @Test
      public void nextCancelRace() {
          for (int i = 0; i < 500; i++) {
              final PublishSubject<Integer> ps1 = PublishSubject.create();
  
              final TestObserver<Integer> to = ps1.concatMapEager(new Function<Integer, ObservableSource<Integer>>() {
                  @Override
                  public ObservableSource<Integer> apply(Integer v) throws Exception {
                      return Observable.never();
                  }
              }).test();
  
              Runnable r1 = new Runnable() {
                  @Override
                  public void run() {
                      ps1.onNext(1);
                  }
              };
              Runnable r2 = new Runnable() {
                  @Override
                  public void run() {
                      to.cancel();
                  }
              };
  
              TestCommonHelper.race(r1, r2, Schedulers.single());
  
              to.assertEmpty();
          }
      }
  
      @Test
      public void mapperCancels() {
          final TestObserver<Integer> to = new TestObserver<Integer>();
  
          Observable.just(1).hide()
          .concatMapEager(new Function<Integer, ObservableSource<Integer>>() {
              @Override
              public ObservableSource<Integer> apply(Integer v) throws Exception {
                  to.cancel();
                  return Observable.never();
              }
          }, 1, 128)
          .subscribe(to);
  
          to.assertEmpty();
      }
  
      @Test
      public void innerErrorFused() {
          Observable.<Integer>just(1).hide().concatMapEager(new Function<Integer, ObservableSource<Integer>>() {
              @Override
              public ObservableSource<Integer> apply(Integer v) throws Exception {
                  return Observable.range(1, 2).map(new Function<Integer, Integer>() {
                      @Override
                      public Integer apply(Integer v) throws Exception {
                          throw new TestException();
                      }
                  });
              }
          })
          .test()
          .assertFailure(TestException.class);
      }
  
      @Test
      public void innerErrorAfterPoll() {
          final UnicastSubject<Integer> us = UnicastSubject.create();
          us.onNext(1);
  
          TestObserver<Integer> to = new TestObserver<Integer>() {
              @Override
              public void onNext(Integer t) {
                  super.onNext(t);
                  us.onError(new TestException());
              }
          };
  
          Observable.<Integer>just(1).hide()
          .concatMapEager(new Function<Integer, ObservableSource<Integer>>() {
              @Override
              public ObservableSource<Integer> apply(Integer v) throws Exception {
                  return us;
              }
          }, 1, 128)
          .subscribe(to);
  
          to
          .assertFailure(TestException.class, 1);
      }
  
      @Test
      public void fuseAndTake() {
          UnicastSubject<Integer> us = UnicastSubject.create();
  
          us.onNext(1);
          us.onComplete();
  
          us.concatMapEager(new Function<Integer, ObservableSource<Integer>>() {
              @Override
              public ObservableSource<Integer> apply(Integer v) throws Exception {
                  return Observable.just(1);
              }
          })
          .take(1)
          .test()
          .assertResult(1);
      }
  
      @Test
      public void doubleOnSubscribe() {
          TestHelper.checkDoubleOnSubscribeObservable(new Function<Observable<Object>, ObservableSource<Object>>() {
              @Override
              public ObservableSource<Object> apply(Observable<Object> o) throws Exception {
                  return o.concatMapEager(new Function<Object, ObservableSource<Object>>() {
                      @Override
                      public ObservableSource<Object> apply(Object v) throws Exception {
                          return Observable.just(v);
                      }
                  });
              }
          });
      }
  
      @Test
      public void oneDelayed() {
          Observable.just(1, 2, 3, 4, 5)
          .concatMapEager(new Function<Integer, ObservableSource<Integer>>() {
              @Override
              public ObservableSource<Integer> apply(Integer i) throws Exception {
                  return i == 3 ? Observable.just(i) : Observable
                          .just(i)
                          .delay(1, TimeUnit.MILLISECONDS, Schedulers.io());
              }
          })
          .observeOn(Schedulers.io())
          .test()
          .awaitDone(5, TimeUnit.SECONDS)
          .assertResult(1, 2, 3, 4, 5)
          ;
      }
  }
  